An abundance of research documents poorer health in minority compared with majority communities. This body of science, however, has not yet been harnessed effectively and consistently to programs that improve minority health. An equally broad and deep research base demonstrates that large proportions of patients do not receive proven-effective health services. We hypothesize that a substantial portion of the racial and ethnic health disparities we observe may be due to greater under use of effective health services among minorities compared with majority populations. Rectifying this under use may represent an effective strategy for reducing disparities. Since 1999, we have been exploring many aspects of this hypothesis in a coordinated research program that has engaged community leaders and groups in Harlem in New York City. Our research teams have measured under use of effective treatments for a variety of conditions highly prevalent in Harlem: heart failure, hypertension, stroke, breast cancer, diabetes, prematurity, post-partum depression, and asthma. We have assessed the roles of a variety of specific factors in causing under-use, for example: hospital programs and characteristics, physician prescribing and referral patterns, community and environmental factors, and patients'knowledge and self-management skills. We have deployed five community-based, controlled trials to assess the impact of focused interventions to remedy these problems. Turning research-funded health improvement interventions into sustained programs has been difficult, but we have succeeded recently in translating two of our effective interventions into sustainable programs. We propose to create the Center for Achieving and Sustaining Improved Health in Harlem. This Center will build on the foundation we have created and will use rigorous research methods to conduct a new generation of intervention trials. These studies will be bolstered by the enthusiastic support of our community partners and their novel strategies to facilitate the enrollment and retention of participants. These trials will focus on enhancing patient self-management skills;an approach our own data are beginning to show is both highly effective and sustainable in Harlem. Our research will also focus on facilitating the sustainability of proven-effective interventions. We aim to create the science that will shorten the time from concept to proven-effective health improvement to sustained health program.